1 - (1 - 1/100)100

There is a calculator on the home page. :)

In my head...-98

To check: $${\mathtt{1}}{\mathtt{\,-\,}}\left({\mathtt{1}}{\mathtt{\,-\,}}{\frac{{\mathtt{1}}}{{\mathtt{100}}}}\right){\mathtt{\,\times\,}}{\mathtt{100}} = -{\mathtt{98}}$$